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CMAQ default initial conditions for selected species near the surface and at sigma levels 0.45 and 0.15. For a model top at 50 mb and a surface pressure of 1,000 mb, these two sigma levels correspond to approximately 480 mb and 190 mb, respectively.
| O3 (ppb) | HNO3 (ppb) | PAN (ppb) | CO (ppb) | NH3 (ppb) | Sulfate (μg/m3) | Nitrate (μg/m3) | |
|---|---|---|---|---|---|---|---|
| Surface | 35 | 0.05 | 0.02 | 80 | 0.1 | 0.6 | 0 |
| Sigma level 0.45 | 60 | 0.07 | 0.01 | 65 | 0.02 | 0.08 | 0 |
| Sigma level 0.15 | 70 | 0.1 | 0 | 50 | 0.01 | 0.04 | 0 |
